You are here

New insight into important chicken virus

Fresh discoveries about Marek's disease could have major implications for the poultry industry, making it possible to breed birds with greater resistance to the disease.

Scientists analysed thousands of genes to pinpoint those that play a role in Marek's disease - a viral infection that costs the global poultry industry more than £1.4 billion a year.

Researchers at The Pirbright Institute, which receives strategic funding from the Biotechnology and Biological Sciences Research Council (BBSRC), were involved in a collaboration with colleagues at The Roslin Institute and the University of Edinburgh. They identified a gene - called IRG1 - that makes chickens more susceptible to the disease.

The gene is thought to cause the death of cells, which can in turn lead to diseases including cancer.

Researchers also found how the Marek's disease virus may also encourage tumour growth.

Professor Venugopal Nair, Head of the Avian Viral Diseases Programme at IAH said "Marek’s is an important disease for the poultry industry and with chicken being the most popular meat eaten worldwide it can have a big impact on global food security. That’s not all though, it's also very interesting as a tool to study the biology behind some cancers."

Chickens and mammals, including humans, have anti-tumour mechanisms, one of which is controlled by a gene called HIC1.

HIC1 switches on lots of other genes which have anti-tumour effects.

Marek's disease virus switches off the genes controlled by HIC1 - in other words, it turns off key genes that would normally work to block tumours.

These genes are also linked to fighting tumours in humans and the study could help research into preventing of some types of cancers in people, which like Marek's disease, are caused by viruses.

Such viruses include the human papilloma virus, which can lead to cervical cancer, and Kaposi's sarcoma, which affects patients with HIV.

Professor Pete Kaiser, of The Roslin Institute who led the research, said "Marek's disease is highly contagious and chickens are becoming increasingly resistant to vaccination. Identifying a gene that increases the risk of Marek's disease could help us breed chickens that are less susceptible to infection.

"Also, learning about how chickens affected by Marek's disease fail to combat the onset of tumours will help us learn more about how certain viruses can trigger cancer in humans."

The research, funded by the Biotechnology and Biological Sciences Research Council, is published in the Journal of Virology.

The Pirbright Institute is the OIE (World Organisation for Animal Health) reference laboratory for Marek's disease.